EP2736561A1

EP2736561A1 - Method and devices for detaching gas accumulations from a blood clot catcher of an extracorporeal blood circulation

Info

Publication number: EP2736561A1
Application number: EP12743676.4A
Authority: EP
Inventors: Soeren Gronau; Dejan Nikolic; Joachim Noack
Original assignee: Fresenius Medical Care Deutschland GmbH
Current assignee: Fresenius Medical Care Deutschland GmbH
Priority date: 2011-07-29
Filing date: 2012-07-27
Publication date: 2014-06-04
Anticipated expiration: 2032-07-27
Also published as: DE102011110472A1; US20130030344A1; DE102011110472A8; WO2013017238A1; WO2013017238A8; EP2736561B1

Abstract

The invention relates to a method for detaching gas accumulations from a blot clot catcher (100) of an extracorporeal blood circulation (1), a control device (29) for carrying out the claimed method, a medicinal treatment device (4) comprising at least one control device (29) and/or working therewith for transmitting a signal or connected thereto for transmitting a signal, a digital storage medium, a computer program product and a computer program.

Description

Besehreibung

Method and devices for removing gas accumulations from a clot trap of an extracorporeal

Blood circulation

The present invention relates to a method according to

Claim 1. It also relates to a control device according to claim 15 and a medical

Treatment apparatus according to claim 16. Furthermore, the present invention relates to a digital

A storage medium according to claim 18, a computer program product according to claim 19 and a computer program according to claim 20.

Extracorporeal blood tubing systems, such as. As used in dialysis or in the use of heart lung machines, often have facilities for the retention of blood clots. These so-called clots

are usually located on the output side of the

Bloodline system and are regularly configured as a fine mesh or mesh. At their mesh gas bubbles can catch, which is undesirable. To prevent or reduce the entrapment of gas bubbles on the clot catcher and / or to detach gas accumulations or gas buildup from the clot trap, methods and design measures are known.

An object of the present invention is to propose a further method of removing gas bubbles or gas accumulations from a clot trap or other component of extracorporeal blood circulation. In addition, suitable inputs or devices, a suitable digital Storage medium, a suitable computer program product and a suitable computer program can be specified.

The object of the invention is achieved by a method having the features of claim 1. It is also solved by means of the control device with the features of

Claim 15, the treatment device with the features of claim 16, the digital storage medium with the

Features of claim 18, the computer program product having the features of claim 19 and the computer program having the features of claim 20.

Thus, according to the present invention, there is provided a method of removing gas accumulations from (or from) a clot trap or other component of an extracorporeal

Bloodstream, which during an extracorporeal

Blood treatment is flowed through or is flowed through in a first flow direction proposed. The method according to the invention comprises generating a flow of a fluid through the component, for example the clot trap, through - or into it - in a second

Flow direction.

The control device according to the invention is suitable and provided and / or designed and / or configured for

Implementation of the method according to the invention.

The medical or medical treatment device according to the invention (in the following also briefly:

Treatment device) has at least one

Control device and / or is hereby in

Signal transmission connected or is in a signal transmission relationship with this. An inventive digital, in particular ^¬ volatile storage medium, particularly in the form of a machine readable carrier, in particular in the form of a

Diskette, CD or DVD or EPRO, with electronically or optically readable control signals can cooperate with a programmable computer system such that the mechanical steps of the method according to the invention are caused.

It can all, some or some of the machine

performed steps of the inventive method be initiated. A computer program product according to the invention has a volatile, volatile or machine-readable program code for initiating the mechanical steps of the method according to the invention, if the

Computer program product on a computer expires.

By a computer program product according to the invention, for example, a computer program stored on a carrier, an embedded system as a comprehensive system with a computer program (eg electronic device with a computer program), a network of computer-implemented computer programs (eg client / server system, Cloud

Computing System, etc.), or a computer on which one

Computer program is loaded, runs, is stored, executed or developed, understood. The term "machine readable carrier" as used herein

is used, in certain embodiments of the present invention, refers to a carrier that has software or / or hardware interpretable data or information contains. The carrier may be a data carrier such as a floppy disk, a CD, DVD, a USB stick, a flashcard, an SD card and the like. A computer program according to the invention has one

Program code for initiating the mechanical steps of the method according to the invention, when the computer program runs on a computer. Under a computer program according to the invention, for example, a physical,

marketable software product that has a program.

It is also true for the computer program product according to the invention and the computer program according to the invention that all, some or some of the mechanically executed steps of the method according to the invention are initiated.

For all subsequent versions, the use of the

Expression "may be" or "may have", etc. synonymous with "is preferably" or "preferably has", etc., and is intended to explain an embodiment of the invention.

Advantageous further developments of the present invention are each the subject of subordinate claims and

Embodiments.

Embodiments of the invention may include one or more of the features mentioned below. In some embodiments of the invention is a

Gas accumulation air or other gas mixture. In some embodiments of the invention, the fluid is a liquid, preferably dialysis fluid or substituate. In some embodiments of the invention, the fluid is a hydraulic fluid, for example from the compliance of the hydraulics (Dialyatseite) of

Treatment device.

In certain embodiments of the invention, the flow of a fluid through the

Through openings of the clot catcher through.

The second flow direction is not the first flow direction in some embodiments according to the invention. In certain embodiments of the invention, the second flow direction opposes the first flow direction. In some embodiments of the invention, a fluid moving in the second flow direction flows into or toward the venous blood chamber.

In some embodiments of the invention, the method includes establishing a pressure by means of the fluid at a time prior to the time of generating the current or the beginning of the current into the second

Flow direction is. In these embodiments, a pressure is first built up, the compensation or at least partial degradation of which is allowed only after reaching a predetermined or desired pressure level, by means of or by generating a fluid flow in the second

Flow direction. The building up of a pressure by means of the fluid thus takes place temporally before the flow is generated in the second flow direction. The pressure built up in this way will be in some

Embodiments of the invention in front of a valve

built up . The pressure built up by means of the fluid is a positive pressure in some embodiments according to the invention.

In some embodiments of the invention, this pressure is an overpressure. In some of the invention

Embodiments, this pressure is above a normal or average operating pressure, which prevails when flowing through the clot trap in the first flow direction or during the blood treatment. In other embodiments of the invention, the pressure is a negative pressure, for example via the membrane of

Blood filter away.

The negative pressure can be a pressure drop from the

Blood compartment of the blood filter towards the

Dialysate compartment of the blood filter.

The negative pressure may arise or have arisen due to a suction effect of the hydraulic system of the treatment device.

In certain embodiments of the invention, the pressure is above a pressure or average pressure generated by the conveyor during the blood treatment. The establishment of a pressure by means of the fluid in some embodiments according to the invention corresponds to a sudden rise in pressure in or at the clot catcher. A sudden increase in pressure is in certain embodiments exclusively on the use of the conveyor

however, not in other embodiments.

In some embodiments of the invention, the method includes generating the flow in the second direction and / or establishing the pressure using a

Blood pump. In these or other inventive

Embodiments, the method comprises generating the flow in the second direction and / or building up the pressure using a hydraulic device of a

medical treatment device. "Use" can be understood here as "by".

In some embodiments of the invention, the method includes closing at least one valve for

Support of the construction of the pressure.

In certain embodiments of the invention, closing is an active process and / or closing is done to help build up the pressure.

The at least one valve to be closed is a venous one in some embodiments according to the invention

Patient tube clamp.

In certain embodiments of the invention, the method includes shorting an arterial section of the extracorporeal blood circuit to a venous section of the extracorporeal blood circuit. In other

According to embodiments of the invention, the method does not include such shorting or bonding. In some embodiments of the invention, the method includes monitoring the level of pressure build-up and / or pressure gradient by means of a suitable one

Facility .

The monitoring of the height of the built-up pressure and / or the pressure gradient goes in certain inventive

Embodiments include or include limiting height.

In some embodiments according to the invention, the monitoring of the level of the built-up pressure and / or the

Pressure gradients by opening the valve or clamp upon reaching a predetermined maximum level of pressure.

The device for monitoring the height of the built up

Pressure and / or the pressure gradient has in certain embodiments of the invention a pressure sensor or consists of such.

In some embodiments of the invention, the method includes opening the valve of the addition site for

Substituate liquid for pre-dilution and / or the valve of the substituate liquid addition site for post-dilution. Their opening can advantageously contribute to the

Flow resistance of the blood filter or dialyzer

advantageous to work around.

In certain embodiments of the invention, the method includes opening the single-needle valve, in some embodiments of the invention, opening the

Venting valve of extracorporeal blood circulation. Your opening can contribute to avoiding that up the suction side of the conveyor builds up a large or even excessive oppression. In other invention

Embodiments remain single-needle valve and / or

Venting valve of extracorporeal blood circulation

closed. This can be advantageous for achieving high

Contribute peak pressures and / or a high pressure gradient over the clot trap.

In certain embodiments of the invention, the method comprises performing all of the aforementioned steps two or more times.

The method comprises in some of the invention

Embodiments The termination of the method after a predetermined number of cycles performed and / or after a predetermined volume of fluid by means of

Conveyor was conveyed in the second flow direction. In certain embodiments of the invention, the method is performed prior to starting a blood treatment, for example in connection with rinsing or priming the extracorporeal blood circulation. "Before starting a blood treatment" means in some

Embodiments of the invention that the

inventive method is completed before the start of treatment of the patient. In certain embodiments of the invention, the

Control device, adjusting devices, measuring devices, control devices or regulating devices, Evaluation devices, comparison devices, and / or

Memory devices for comparison data on.

The treatment device according to the invention is in some embodiments a blood treatment device,

in particular as a device for apheresis or dialysis, again in particular for hemodialysis, hemofiltration,

Hemodiafiltration, or designed for acute dialysis. In some embodiments of the invention

Treatment device is the conveyor as

Designed blood pump. In certain inventive

Embodiments, it is designed as a roller pump. The invention relates to a hose configuration and a method, which advantageously facilitates the venting of clot traps: The method is based on the fact that the flow direction z. B. when filling / rinsing the

Disposables in the clot catcher is temporarily reversed.

A detachment of gas bubbles or accumulations by means of the method according to the invention or the free-flushing method is possible in certain embodiments of the invention at any points of the extracorporeal blood circulation and of any components of the extracorporeal blood circulation. These sites or components include the blood filter or dialyzer. These sites or components include, in particular, those through which - or into which - a pressure wave produced according to the invention runs. The present invention is thus not limited to detaching gas bubbles or accumulations from the clot trap, even if parts of the present description explicitly refer to a

Clots are turned off, but not restrictive to understand. Other components or components of the extracorporeal blood circulation or the blood tubing set, such as the blood filter, can by means of

inventive method and / or the inventive devices are freed of gas bubbles or accumulations. The present invention thus also extends to this.

Some or all embodiments of the invention may include one or more of those mentioned above or below

Have advantages.

Thus, in contrast to the provision of coatings of the state of the art, the method according to the invention leads to the ventability of the clot trap by modifying the wettability of the material of the clot trap

to improve, advantageously not to a generally increased passability of air bubbles through the

Clot catcher; The latter would be in forward mode

undesirable.

The method may be used during preparation of the disposables, e.g. B. in the form of extracorporeal blood circulation, or the treatment device can be performed without the user would have to intervene.

The elimination of residual air advantageously prevents possible unwanted air infusion in the treatment (eg induced by applying flow rates of blood flows during the treatment which are higher than flow rates during the preparation of the

Devices). The elimination of residual air in the extracorporeal system can also advantageously improve the hemocompatibility of the entire system. The control of the venting over when closed

Terminal occurring pressures advantageously prevents bursting of the hose system. This is relevant because

Hose reel pumps may have significantly higher occlusion pressures during backward conveyance than during normal operation.

Also in the context of the backward promotion, the function of the arterial pressure measurement in the overpressure range can be tested. B. before opening the venous clamp the

Single-needle valve to be closed. In the overall system then sets a positive residual pressure; this can be determined and compared with arterial and venous pressure measurement.

The consequences of a difficult passage of residual air through the mesh of a clot trap according to the invention, for. B. due to existing buoyancy, according to the invention

also be counteracted advantageous.

The present invention will be explained in the following with reference to the accompanying drawings, in which identical reference numerals designate the same or similar components, by way of example. In the partially simplified figures:

FIG. 1 shows an example of a blood clot trap in FIG

Section from which gas attachments can be released by means of the method according to the invention; FIG. 2 shows, schematically simplified, an extracorporeal blood circulation for releasing gas adherences from a blood clot trap. Fig. 1 shows a section through a arranged in a housing 200 blood clot (short also

Clot trap) 100. The clot trap 100 has a screen surface 101, which has passage openings 103 and a section 105 without such passage openings. The inflow region of the clot catcher 100 is connected to the

Reference numeral 109, the discharge area marked 111. At the openings 103 air bubbles can hold. These can be released from the passage openings by means of the method according to the invention.

Fig. 2 shows schematically simplified an extracorporeal blood circulation 1, which at least in sections thereof is part of a blood cassette 2. To treat a patient, the blood cassette 2 is in a medical

Blood treatment device (in short: device) 4

inserted.

The extracorporeal blood circulation 1 comprises an arterial patient tube clamp 6 of an arterial section 9, furthermore a venous patient tube clamp 7 of a venous section 23.

A blood pump 11 is provided in the arterial portion 9, a substituate pump 17 is connected to a substituate line. The Substituatleitung can by means of a

automatic substituate ports 18 are connected to a substituate source. By means of the substituate pump 17 can

Substituate by predilution or by postdilution and the associated addition points 13 and 14 are introduced into line sections of the bloodstream 1.

In the bloodstream 1, a blood filter 19 is turned on. This has a connected to the arterial portion 9 and the venous portion 23 blood chamber 19a. A dialysate chamber 19b is connected to a dialysate feed line 31a leading to the dialysate chamber 19b and one of the

Dialysate chamber 19b continuing dialysate drain line 31b. The venous portion 23 is in

Fluid communication with a venous blood chamber 24 of the extracorporeal blood circuit 1.

The venous blood chamber 24 is at its outflow side with the clot catcher 100 in fluid communication and / or has such.

The venous blood chamber 24 is in fluid communication with and / or has a single-needle valve 35 (SN valve) on its inflow side. The venous blood chamber 24 is also at its inflow side with a

Venting valve 24a in fluid communication and / or has such. Air detectors 25a and 25b are provided in the arterial portion 9 and the venous portion 23, respectively.

A control device 29 according to the invention is

shown schematically. She is in contactless

Signal connection (non-contact) and / or in

Contact connection with the components required for carrying out the method according to the invention, such as sensors, clamps, valves, blood pump, etc. The Dialysatzulaufleitung 31 a has a valve V 24, by means of which the flow within the

DialysateZulaufleitung 31a can be prevented. The

Dialysate drain line 31b has a valve V25 by means of which the flow within the dialysate drain line 31b can be prevented.

The Dialysatzulaufleitung 31 a is further by means of another, internal machine valve with a

Compressed air source 26 connected.

Pressure sensors 33a and 33b measure the pressure in the arterial section 9 and in the venous section 23, respectively. A pressure sensor 37 measures the pressure in the dialysate inlet duct 31a.

The dialysate circuit has a purge valve V33.

For carrying out the method according to the invention, in certain embodiments in arrangements as shown in FIG. 2, the arterial portion 9 and the venous

Section 23 shorted together. The purge valve V33 can be closed. Subsequently, the direction of rotation of the blood pump 11 is reversed. The blood pump 11 promotes

Liquid against the meantime closed venous patient tube clamp 7 in the in Fig. 2 with arrow

displayed direction. The pressure built up in this case is limited by the pressure sensor present in the device 4: When a defined maximum pressure is reached, the venous patient tube clamp 7 is opened. The Indian

Compliance between blood pump 11 and venous

Patient tube clamp 7 caught pressure builds up

abruptly into the venous blood chamber 24 into it. He can There lead to partly high and very high peak flows, which are considerably larger than those rivers, which in promotion by means of the blood pump 11 in normal operation of the

Device 4 occur in the first conveying direction.

Due to the peak flows, air bubbles that are on the output side (in Fig. 2 at the bottom of the

Clot catcher) of the clot trap 100 are completely or at least partially entrained over the bottlenecks of the clot trap 100.

In the embodiment proposed here of the

The method according to the invention is an application of

Substituate pump 17 is not provided and / or not

required. Valves of addition points 13 and 14 for

Substituate liquid in pre-dilution or postdilution (also referred to as pre-valve and post-valve) are open to the flow resistance of the blood filter 19, also as

Dialyzer called to work around. The single-needle valve 35 and the vent valve 24a are opened to provide a strong vacuum build-up on the suction side of the

To avoid blood pump. In order to increase the peak flows, the single-needle valve 35 and / or the

Vent valve 24a also be closed to the

Pressure gradients over the clot catcher 100 continue to increase.

The deaeration process described above can - if necessary - be repeated one or more times. The inventive method is particularly effective in an arrangement of the clot trap such that

Accumulate air bubbles in a place where they turn when reversed the flow through the flow is particularly unhindered

be carried away.

In a further embodiment according to the invention, flushing of the clot catcher 100 takes place by means of a

Liquid, which for this purpose the hydraulic or

Hydraulic device of the treatment device 4 is removed. In this procedure, the valves V24 and / or V25 may be open. At the same time, the single-needle valve 35 and / or the ventilation valve 24 may be closed. The fluid is also conveyed in this embodiment by the backward or in the second flow direction promoting blood pump 11. This builds possibly also the above

described overpressure.

This differs from the further embodiment of the invention described below. At this

Embodiment - unlike in Fig. 2 shown - the arterial portion 9 and the venous portion 23rd

advantageously not shorted together or

connected to each other (though this is also true for this

Embodiment quite possible and is also encompassed by the present invention, for example in reverse-running blood pump 11). The construction of the

required pressure of the fluid in the clot trap 100 is generated in this embodiment by means of a negative pressure on the membrane of the blood filter 19, which is achieved by the use of the hydraulics of the treatment device 4. Used reference signs:

1 extracorporeal blood circulation

2 blood cassette

4 device or medical treatment device

6 arterial patient tube clamp

7 venous patient tube clamp

9 arterial section

11 blood pump

13 addition point for substituate liquid (predilution)

14 addition point for substituate liquid (postdilution)

17 Substituent pump

18 automatic substituate port

19 blood filter or dialyzer

19a blood chamber

19b dialysate combs

23 venous section

24 venous blood chamber

24a ventilation valve

25a arterial air detector

25b venous air detector

26 compressed air source

29 Control or regulation device

31a Dialysatzulaufleitung

31b dialysate drain line

33a pressure sensor

33b pressure sensor

35 single-needle valve

37 pressure sensor

V24 valve

V25 valve

V33 flushing valve

100 clot trap Screen area

Through openings

Section without passages Inlet area of the clot trap Outflow area

casing

Claims

claims

1. A method for separating gas accumulations from a

Component of an extracorporeal blood circulation (1), for example a clot trap (100), which is perfused or flowed through during an extracorporeal blood treatment in a first flow direction, comprising the steps of: - generating a flow of a fluid through the

Component, for example the

Clot trap (100), through or into it in a second flow direction. 2. The method according to claim 1, with the further step:

Build up a pressure by means of the fluid

Generating the current in the second

Flow direction.

3. The method according to claim 1 or 2, with the further

Step:

Close at least one valve to

Support of the construction of the pressure.

4. The method according to any one of the preceding claims, comprising the step of: - Shorting an arterial portion (9) of the extracorporeal blood circulation (1) with a venous portion (23) of the extracorporeal

Blood circulation (1). Method according to one of the preceding claims, with the step:

Generating the flow in the second direction and / or building up the pressure or negative pressure using a blood pump (11) and / or using a hydraulic device of a medical treatment device (4).

Method according to one of the preceding claims, with the step:

Monitoring the level of pressure built up and / or the pressure gradient by means of a device.

Method according to one of the preceding claims, with the step:

Opening the valve of a substituate addition point (13) for predilution and / or the valve of an addition point (14) for

Substituate liquid for post-dilution or one or more further valves for opening a communication connection with a blood filter (19)

Method according to one of the preceding claims, with the step:

Opening a single-needle valve (35).

9. The method according to any one of the preceding claims, comprising the step: Opening a venting valve (24a).

10. The method according to any one of the preceding claims, comprising the step:

Conveying fluid across the membrane of the

Blood filter (19) by means of or using the hydraulic device of

Treatment device (4) as a conveyor.

11. The method according to claim 10, wherein by means of

Hydraulic device of the treatment device (4) a negative pressure over the membrane of the blood filter (19) is generated.

12. The method according to any one of the preceding claims, comprising the step: two or more times performing all the steps of one or more of the preceding claims.

13. The method of claim 12, comprising the step:

Canceling the method after a predetermined number of cycles performed and / or after a predetermined volume of fluid has been conveyed by the conveyor in the second flow direction.

14. The method according to any one of the preceding claims, comprising the step: Perform the procedure before starting a

Blood treatment session.

Control device (29) for performing a

Method according to one of the preceding claims.

Medical treatment device (4), which

at least one control device (29) and / or is in signal transmission with this or is connected to the signal transmission.

Medical treatment device (4) after

Claim 16, which as a blood treatment device, in particular as a device for apheresis or dialysis, in turn, in particular for hemodialysis, hemofiltration, hemodiafiltration or for acute dialysis, designed.

Digital storage medium, in particular in the form of a floppy disk, CD or DVD or EPROM, with electronically readable control signals, configured to cooperate with a programmable computer system such that the mechanical steps of a method according to one of claims 1 to 14 are initiated.

Computer program product with one on one

machine-readable carrier stored program code for initiating the automated steps of

The method according to any one of claims 1 to 14, when the computer program product runs on a computer. Computer program with a program code for initiating the mechanical steps of a device according to the invention

Method according to one of claims 1 to 14, when the computer program runs on a computer.